Electrochemical Reactions in the Cold

Joseph Barrella, Philip H. Gow. "Integral Battery Thermal Management." 1-5.
http://www.faqs.org/patents/app/20080268333

(freezer) (refrigerator)


(room temperature)

Electrochemical Reactions in Cold. Wyatt Wenzel and Bryce Holstad. The effect of temperature on an electrochemical reaction was tested by first creating a battery from aluminum nitrate, sodium chloride, aluminum foil, an iron nail, and a salt bridge made of a curved glass tube and a folded paper towel. This apparatus was then placed in three seperate temperature environments; room temperature, refrigerator, and a freezer. The hypothesis revolved around the notion that the cold temperature would affect the internal resistance of the battery; the ability of the electrons to flow between the anode (aluminum foil) and the cathode (iron nail). This was measured by a voltmeter. It was predicted that the colder temperatures would cause the internal resistance to be greater, meaning that the voltage of the battery would decrease.The choice of anode and cathode proved to present a slightly inconsistent pair, voltage strikingly sporadic from one environment to the next. The initial leaps in temperature, in general, facilitated steep decline in voltage as well. Decreasing temperature didn ’t always mean a decrease in voltage, though, as displayed when the temperature of the freezer submerged below 0 degrees Celsius, yet the voltage rose. Keywords: salt bridge, electron transfer, anode, cathode, voltmeter, voltage, electrochemical reaction, internal resistance